Die casting machine



G. W. BUNGAY DIE CASTING MACHINE April 24, 1934 Filed May 5,, 1831 5 Sheets-Sheet 1 ATTORNEY 'Aprfl 24,1934. 6. w. BUNGAY m msmm MACHINE Filed Efiay 5 I EN/ NT Z AWQEQNEY rifi 24, 1934. G. w.-- BUNGAY DIE CASTING MACHINE Filed May 5, 1931 5 Sheets-Sheet 3 14mm I Patented Apr. 24, 1934 outrun DEE @ASTING MACHINE George W. Bungay, l lainfield N. 3., assignor to Aluminum @ompany of America, .littsburgh, Pin, a corporation of Pennsylvania Application May 5, 1931, Serial No. 535,112

My invention relates to die casting machines and particularly that type of die casting machine utilizing two-piece dies having a center gate in one half thereof and using fluid pressure for forcing the metal into the die. It also relates to that type of die casting machine having a movable pressure chamber or ladle whereby, after the molten metal has been permitted to enter the pressure chamber, it is forced by fluid pressure from the pressure chamber into the die. Erossure chambers which are movable, so as to permit the nozzle to dip into the molten metal to receive a charge, and afterwards raised above the surfaceoi the molten metal and into contact with the gateof the die, so' that the metal may be forced from the pressure chamber into the die,

are old.

By means, however, of my improvement I am able to dip the pressure chamber into the pot or raise it above the surface of the molten metal in such a position that the nozzle may be cleaned of dross and other impurities before bringing the nozzle into contact with the gate of the die. The nozzle of the pressure chamber is also held firmly against the die head during casting so that substantially no leakage occurs between the nozzle and the gate. By means of invention the molten metal does not slop or drip from the nozzle when it is being moved into contact with the die head. I

Other advantages will appear from the following description and the appended claims.

Figure 1 shows an elevation of my improved pressure chamber and the mechanism for operating the same with the melting pot and die head partly in section.

Figure 2 is an elevation of my improved pressure chamber showing the nozzle dipping into the molten metal, the die head and the melting pot being partly in section.

Figure 3 is a plan view of my invention.

Figure 4 shows a detail of the handle and latch mechanism.

Referring to the drawings, a heating chamber or furnace 1 is provided with a melting pot 2. Supported adjacent the melting pot 2 is a die head 3 provided with the rods One half of a two-piece die having a gate in the center (not shown) is adapted to be fastened to the die head 50 3. The other half of the die (not shown) is adapted to slide along the rods 4 in the usual manner whereby the die may be opened and closed. This method of opening and closing the die is old and well-known and does not need any illustration or further description.

Supported for movement in the melting not 2 is a pressure chamber or gooseneck 5. This pros sure chamber is provided with a top portion at which is secured to the pressure chamber by means of bolts '7. The top portion is provided with two fins 8 and 9. The fin 8 is provided with two sockets 10 and 11, the purpose of will hereafter be described. The fin 9 is provided with a flat rail-like portion 12.

The furnace 1 is provided with a top plate Secured to the top plate 13 are split bearings 15. A fluid pressure cylinder 16 is provided with. hollow trunnions 1'7, 18 adapted to turn in the split bearings 14, 15.

The cylinder 16 is provided with a piston (not shown) to which is connected a piston rod 19, one

. end of which is secured in the socket 11 by means of a set screw 20. Mounted on the cylinder id is a bracket 21 carrying a bearing 22. rod. 23 is adapted to slide in the bearing 22, one end of the rod 23 being secured in the socket it) by means of a set screw 24. The purpose or the rod 23 is to hold the gooseneck in alignment d reciprocation. The fluid used to operate piston of the fluid pressure cylinder it m y be compressed air, water, or any other suite The fluid is supplied to and discharged tr cylinder 16 by means of pipes 25, 2-5 secured to the trunnions i7, 18 of the ey -nd..r by means of unions 27, 28. While the pipes 26 are stationary, the rocking oi the trunni i7, 18 is permitted due to the connections 2 Mounted on the plate 13 is a bracket 29 vided with a bearing 30. Mounted on the br 29 is a lug 31 having a hole therein for the tion of a bolt 32. Mounted on the means of the bearing 30 is a stud on the stud 33 is a yolked arm 34 provided wit. bearings 35, 36. The other end or" the yollred arm is provided with a short arm or extension 3'? ing a slot 38 therein. The bolt 32 extends through the slot 38 of the short arm 37. This bolt 32 is provided with a nut 39. By adjusting the nut 39 the arm 34 may be. raised or lowered, the purpose of which will hereafter be explained.

Mounted in the bearings 35, 36 of the arm 34 is an eccentric shaft 40.. This eccentric shaft is provided at its innerend with a roller 41 on which the rail 12 of the pressure chamber 5 is adapted to ride. The eccentric shaft 40 is provided wi h a crank 42 adapted to be operated by a hands Pivoted on the crank 42 by means of a pivot 4-1 is a lever 45. The handle 43 is slidably mounted on a hollow stud 46 secured to the crank 42. Mounted inside of the hollow stud 46 is a stud n, 110

one end of which is secured to the lever 45 by means of a nut 48. The other end is secured to the handle 43 by means of a screw 49. A spring is positioned between the handle 43 and the hollow stud 46 and tends to force the end 51 of the lever 45 into engagement with a slot 52 in the end of the bearing 35. Thus, when the handle 43 is pushed inwardly to compress the spring 50, the end 51 of the lever 45 is caused to move out of the slot 52, permitting the crank 42 to be operated. When the lever is swung through the necessary arc, the end 51 of the lever 45 will again engage the slot 52 at the opposite end thereof and will hold the crank 42 in the predetermined position. A boss on the end of the bearing 35 engages the crank 42 at both limits of its movement and supports the gooseneck in elevated or lowered position in accordance with the position of the crank 42. The latching mechanism 51 merely holds the crank against accidental movement.

The gooseneck or pressure chamber 5 is provided with a nozzle 53. This nozzle 53 is tapered at one end at 54 to fit into the gooseneck and at the other end 55 to fit into a gate piece 56 of the die head. This gate piece 56 is tapered at one end at 57 to receive the taper 55 of the nozzle 53, and is tapered at the other end at 58 to permit the withdrawal of the sprue with the casting. The head of the cover 6 of the gooseneck 5 is provided with an opening 59 adapted to receive a flexible connection not shown to supply the compressed air or other suitable pressure means to force the metal from the pressure chamber 5 through the nozzle, through the gate. into the die.

The operation of the device is as follows:

Assuming the pressure chamber to be in the position shown in the full lines (Figure 1), the casting having been completed and the pressure chamber ready for another charge of metal, the operating fluid is admitted into the cylinder 16 by either of the pipes 25. 26 by means of a suitable valve system (not shown). The piston is retracted, causing the piston rod 19 to move the pressure chamber 5 rearwardly. The pressure chamber will move in a substantially horizontal direction due to the fact that the track 12 rides along the roller 41. When the piston has finished its movement and the pressure chamber has assumed the position shown in the dotted lines (Figure l) the operator presses the-handle 43, releasing the latch 51, rotates the crank 42, thereby rotating the eccentric shaft 40 and lowering the nozzle of the gooseneck into the molten metal, as shown in Figure 2.

After the charge of molten metal has flowed into the pressure chamber, the handle 43 is again pressed, releasing the latch 51, and the crank 42 is rotated to the position shown in Figure 3, thereby raising the pressure chamber to the position shown in the dotted lines of Figure 1. The piston in the cylinder 16 is then operated by means of the fluid pressure to move the pressure chamber forward and into register with the opening 5'7 of the gate 56. Since fluid pressure is used to move the pressure chamber 5 into casting position it will be held firmly against the taper 57 of the gate 56, so that no leakage can occur during the casting operation. By use of the fluid.pressure cylinder 16, no careful adjustment is necessary as in the case where a pressure chamber is held against a gate by means of toggles and levers. Air or other fluid pressure is then admitted through the opening 59 from the source of supply by means of a valve (not shown) and the metal is forced from the gooseneck 5 through the nozzle 53, through the gate 56, and into the die.

It is obvious that while the pressure chamber is in the position shown in the dotted lines of Figure 1 and before it is moved forwardly to register with the gate 56, the nozzle may be cleaned of any adhering dross which it may have collected from the surface of the molten metal. This cleaning permits a tight joint between the taper 55 of the nozzle and the taper 57 of the gate 56.

It is obvious that the cylinder 16 may be built of any size which may be necessary to firmly hold the nozzle in contact with the gate 56 regardless of the casting pressure applied to force the molten metal from the pressure chamber into the die. It is also obvious that there will be no drip or splash of molten metal from the pressure chamber while the pressure chamber is beingmoved forward into register with thegate as ocours with some types of die casting apparatus having movable pressure chambers.

If the connection between the nozzle 53 and the gate 56 is to be tight enough to prevent leakage during casting, both the nozzle 53 and the beveled surface of the gate 56 must be kept clean from metal and dross. By preventing the slopping of the molten metal from the nozzle as the nozzle is being brought into contact with the gate, any deposit of metal on the surface 57 of the gate 56 is prevented.

The adjustment of the nut 39 on the bolt 32 will cause the arm 34 to be raised or lowered, so as to permit the nozzle 53 of the pressure chamber 5 to exactly register with the gate 56 of the a die hand. Any expansion or contraction of the pressure chamber due to the intense heat of the molten metal can be readily compensated for by adjustment of the nut 39.

Since it is obvious that various changes and modifications may be made in the above descrip-. tion without departing from the nature and spirit thereof, this invention is not restricted thereto except as defined in the appended claims.

I claim:

1. In a die casting machine, a melting pot, a, pressure chamber pivoted adjacent the melting pot, a guide member rigidly connected to said pressure chamber, a rotating member mounted at one side of the said melting pot and operatively connected to said guide member, and means for reciprocating said pressure chamber into and out of contact with the gate of a die, said rotating member being adapted to move said pressure chamber independently of the reciprocating means into and out of the melting pot.

2. In a die casting machine, a melting pot, pressure chamber pivotally mounted at one end, a support for the other end of the pressure chamber pivotally mounted at one side oi the said melting pot, means for reciprocating the pressure chamber along said support, and means for moving said support so that the pressure chamber. is rotated on its pivot independently of the reciprocating movement.

3. In a die casting machine, a melting pot, a pressure chamber having a pivotal support at one end and a rotatable support at the other end mounted at one side of the said melting pot, means for moving the pressure chamber horizontally along said rotatable support, and means for rotating said rotatable support so that the pressure chamber is rotated on its pivot independently of the horizontal movement.

4. In a die casting machine, a melting pot, a pressure chamber having a guideway at one end and pivotally supported at the other end, arotatable support mounted at one side of the said melting pot and adapted to cooperatewith said guideway, means for moving the guideway of said pressure chamber horizontally along said rotatable support, and means for rotating said support so thatthe pressure chamber is rotated on its pivot independently of the horizontal movement.

5. In a die casting machine, a melting pot, a pressure chamber pivotally mounted adjacent said melting pot and having a nozzle, a guideway on the 'pressure chamber, fluid pressure means for moving said pressure'chamber horizontally, and means cooperating with -said guideway to guide the horizontal movement of said pressure chamber, said means operating independently of the horizontal position of said pressure chamber to swing the pressure chamber on its pivot' so that the nozzle may be lowered into and raised out of the melting pot.

6. In a die casting machine, a melting pot, a pressure chamber pivotally mounted in said melting pot, a guideway on the pressure chamber, a rotatable support for said guideway mounted at one side of the said melting pot, fluid pressure means for moving said pressure chamber horizontally, and means cooperating with said guideway and said rotatable support to swing the pressure chamber on its pivot whereby the nozzle may be lowered into or raised out of the melting pot.

'7. In a die casting machine, a melting pot, a pressure chamber, a; guidevvay on said pressure chamber, a support pivotally mounted at one side or" the said melting pot and operatively connected to said guideway, pivotally mounted fluid pressure means operatively connected to said pressure chamber, means for operating said fluid pressure means to move the pressure chamber horizontal- 1y along said guideway, and means for rotating said pivotally mounted support so that the pressure chamber may be lowered into and raised out of the melting pot.

8. In a die casting machine, a melting pot, a pressure chamber mounted for reciprocal and pivotal movement, a guideway on said pressure chamber, a fluid pressure cylinder operatively connected to said pressure chamber, an eccentric shaft mounted at one side of the said melting pot, a roller mounted on said eccentric shaft adapted for engagement with said guideway, means for operating said fluid pressure cylinder to move the pressure chamber substantially horizontally on said roller, and means for rotating said eccentric shaft so that the pressure chamber may swing on its pivot into or out of the melting pot.

9. In a die casting machine, a melting pot, a pressure chamber pivoted adjacent the melting pot, a guideway on said pressure chamber, an eccentric shaft rotatably mounted at one side of the said melting pot and adjacent the guideway, a roller mounted on said eccentric shaft adapted for engagement with said guideway, a pivotally supported fluid pressure cylinder operatively connected to said pressure chamber, means for operating said fluid pressure cylinder .to move said pressure chamber substantially horizontally on said roller into and out of contact with the gate of a die, and means for rotating said eccentric shaft so that the pressure chamber. may be lowered into or raised out of the melting pct.

10. In a die casting machine, a melting pot, a pressure chamber pivoted adjacent the melting pot, a guideway on said pressure chamber, a movable support mounted at one side of the said melting pot and operatively connected to said guideway, a pivotally supported fluid pressure cylinder operativelvconnected to, said pressure chamber, means for operating'said fluid pressure cylinder to move said pressure chamber horizontally into and out of contact with the gate of a die, and means for moving said support along said guideway so that the pressure chamber may be lowered into or raised out of the melting pct.

11. In a die casting machine, a melting pot, a pressure chamber terminating in a nozzle, a support for said pressure chamber mounted at one side of the said melting pot and adjacent said nozzle, a pivotally supported fluid pressure cylinder operatively connected to said pressure chamber, and guide means independent of said support associated with said pressure chamber and the fluid pressure cylinder to hold the pressure chamber in alignment and prevent rotation thereof about the axis of said fluid pressure chamber during its movement.

12. In a die casting machine, a melting pot, a pressure chamber pivotally mounted adjacent said melting pot and having a nozzle, guide means associated with said pressure chamber, means for moving said pressure chamber horizontally, a support cooperating with said guide means to guide the horizontal movement of said pressure chamber, and means to raise or lower said support to swing the pressure chamber on its pivot independently of the horizontal position thereof so that the nozzle may be raised out of or lowered into the melting pot.

GEORGE W. BUNGAY. 

